Plasma-Distributing Structure in a Resonator System

Abstract

An example system can include a radio-frequency power source, a resonator, and a plasma-distributing structure. The resonator can include an electrode having a first concentrator. The resonator can be configured to provide a plasma corona when excited by the power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter of a resonant wavelength of the resonator. The plasma-distributing structure can be arranged proximate to the plasma corona provided by the resonator and include a second concentrator. When the power source excites the resonator with the signal, an electric field can be concentrated at the first concentrator and the plasma corona can be provided proximate to the first concentrator. Further, when the plasma corona is provided proximate to the first concentrator and the plasma-distributing structure is at a predetermined voltage, an additional plasma corona can be established proximate to the second concentrator.

What is claimed is: 
     
         1 . A system comprising:
 a radio-frequency power source;   a resonator configured to be electromagnetically coupled to the radio-frequency power source and having a resonant wavelength, the resonator including:
 a first conductor, 
 a second conductor, 
 a dielectric between the first conductor and the second conductor, and 
 an electrode configured to be electromagnetically coupled to the first conductor and including a first concentrator, wherein the resonator is configured to provide a plasma corona proximate to the first concentrator when excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter (¼) of the resonant wavelength; and 
   a plasma-distributing structure including a second concentrator, the plasma-distributing structure being arranged proximate to where the plasma corona is provided by the resonator,   wherein when the radio-frequency power source excites the resonator with the signal, an electric field is concentrated at the first concentrator and the plasma corona is provided proximate to the first concentrator, and   wherein when the plasma corona is provided proximate to the first concentrator and the plasma-distributing structure is at a predetermined voltage, an additional plasma corona is established proximate to the second concentrator.   
     
     
         2 . The system of  claim 1 , further comprising a controller configured to carry out operations that include:
 causing the predetermined voltage to be provided at the second concentrator; and   causing the radio-frequency power source to excite the resonator with the signal.   
     
     
         3 . The system of  claim 1 , wherein the resonator is selected from the group consisting of: a coaxial resonator, a dielectric resonator, a rectangular-waveguide cavity resonator, a parallel-plate resonator, and a gap-coupled microstrip resonator. 
     
     
         4 . The system of  claim 1 , wherein the predetermined voltage ranges from 20 kV to 100 kV or from −20 kV to −100 kV, relative to a ground voltage. 
     
     
         5 . The system of  claim 1 , further comprising a direct-current power source configured to provide the predetermined voltage at the first concentrator and the second concentrator. 
     
     
         6 . The system of  claim 1 , wherein the second concentrator tapers to an edge. 
     
     
         7 . The system of  claim 1 , wherein the second concentrator tapers to a point. 
     
     
         8 . The system of  claim 1 , wherein the plasma-distributing structure includes a plurality of segments, each having a respective second concentrator configured to sustain a respective additional plasma corona. 
     
     
         9 . The system of  claim 8 , wherein the plurality of segments includes a plurality of helical ridges disposed about a longitudinal axis of the combustion chamber and around the interior wall of the combustion chamber 
     
     
         10 . The system of  claim 1 , further comprising:
 a combustion chamber; and   an insulating material configured to couple the plasma-distributing structure to an interior wall of the combustion chamber and further configured to electrically insulate the plasma-distributing structure from the interior wall of the combustion chamber.   
     
     
         11 . The system of  claim 10 , wherein a shape of the second concentrator is selected to cause the additional plasma corona to have a predetermined shape within the combustion chamber. 
     
     
         12 . The system of  claim 10 , wherein the plasma-distributing structure and the interior wall of the combustion chamber have a same shape. 
     
     
         13 . The system of  claim 1 , wherein the plasma-distributing structure is a first plasma-distributing structure and the predetermined voltage is a first predetermined voltage, the system further comprising:
 a second plasma-distributing structure including a third concentrator, the second plasma-distributing structure being arranged within the combustion chamber and proximate to where the additional plasma corona is established,   wherein when the additional plasma corona is established and the second plasma-distributing structure is at a second predetermined voltage, another additional plasma corona is established proximate to the third concentrator and within the combustion chamber.   
     
     
         14 . The system of  claim 1 , wherein the combustion chamber has a longitudinal length, wherein the plasma-distributing structure is a first plasma-distributing structure that has a first shape and that is arranged at a first location along the longitudinal length of the combustion chamber, the system further comprising:
 a second plasma-distributing structure that has a second shape, different from the first shape, the second plasma-distributing structure being arranged at a second, different location along the longitudinal length of the combustion chamber.   
     
     
         15 . The system of  claim 14 , wherein the first plasma-distributing structure includes a plurality of segments arranged in an annular shape, and wherein the second plasma-distributing structure includes a single, annular plasma-distributing structure. 
     
     
         16 . The system of  claim 1 , wherein the plasma-distributing structure includes a plurality of segments, each having a respective second concentrator configured to sustain a respective additional plasma corona, and each electrically coupled to a direct-current power source, the system further comprising a controller configured to carry out operations including:
 causing the direct-current power source to sequentially bias the respective segments with the predetermined voltage, according to a desired plasma-distribution sequence, so as to cause the additional plasma corona to be established sequentially at the respective segments according to the desired plasma-distribution sequence.   
     
     
         17 . The system of  claim 16 , wherein the direct-current power source includes a plurality of direct-current power sources, each corresponding to a respective segment of the plurality of segments and configured to bias the respective segment with the predetermined voltage. 
     
     
         18 . The system of  claim 16 , wherein the direct-current power source includes:
 a single direct-current power source configured to bias the plurality of segments with the predetermined voltage.   
     
     
         19 . The system of  claim 18 , wherein the direct-current power source further includes:
 a plurality of switches, each switch of the plurality of switches corresponding to a respective segment and being configured to control biasing of the respective segment with the predetermined voltage.   
     
     
         20 . A system comprising:
 a radio-frequency power source; and   a resonator configured to be electromagnetically coupled to the radio-frequency power source and having a resonant wavelength, the resonator including:
 a first conductor, 
 a second conductor, 
 a dielectric between the first conductor and the second conductor, and 
 an electrode configured to be electromagnetically coupled to, and disposed at, a distal end of the first conductor, the electrode including a concentrator having a concentrator shape configured to define a shape of a plasma corona provided by the resonator, 
   wherein the resonator is configured such that, when the resonator is excited by the radio-frequency power source with a signal having a wavelength proximate to an odd-integer multiple of one-quarter (¼) of the resonant wavelength, the resonator provides the plasma corona proximate to the concentrator.   
     
     
         21 . The system of  claim 20 , further comprising a controller configured to carry out operations, the operations including:
 causing the radio-frequency power source to excite the resonator with the signal.   
     
     
         22 . The system of  claim 20 , wherein the concentrator terminates at one or more edges distal from a location at which the electrode is configured to be configured to be electromagnetically coupled to the first conductor. 
     
     
         23 . The system of  claim 20 , wherein the concentrator shape defines a structure selected from the group consisting of: a single linear blade, a single curved blade, a cross-shaped blade, one or more sawtooth protrusions, one or more cone protrusions, one or more needle protrusions, one or more helical protrusions, and one or more wave-shaped protrusions. 
     
     
         24 . A method comprising:
 exciting a resonator with a radio-frequency signal having a wavelength proximate to an odd-integer multiple of one-quarter (¼) of a resonant wavelength of the resonator, such that an electric field is concentrated at a first concentrator of the resonator and a plasma corona is provided proximate to the first concentrator; and   providing a predetermined voltage at a second concentrator of a plasma-distributing structure that is arranged proximate to the plasma corona provided by the resonator, so as to establish an additional plasma corona proximate to the second concentrator of the plasma-distributing structure.   
     
     
         25 . The method of  claim 24 , wherein the plasma-distributing structure is disposed within a combustion chamber, and wherein the plasma-distributing structure is coupled to an insulating material configured to electrically insulate the plasma-distributing structure from an interior wall of the combustion chamber, the insulating material being disposed between the plasma-distributing structure and the interior wall of the combustion chamber. 
     
     
         26 . The method of  claim 25 , further comprising:
 inputting fuel into the combustion chamber, whereby the additional plasma corona ignites the fuel so as to cause combustion of the fuel.